The field of the invention generally pertains to a carrier assembly. The invention relates more particularly to a carrier assembly hinge-mounted to one corner of the rear end of a trailer. The carrier assembly is capable of swinging outward and away from the rear end of the trailer to provide uninhibited access to the trailer's rear cargo area.
Carrier assemblies have been mounted to the rear end of vehicles in a variety of ways to provide additional carrying and/or storage space without inhibiting access to the rear cargo area of a vehicle. Many carrier assemblies accomplish this by providing a way to swing the carrier assembly away from the rear end of the vehicle to gain access to the rear cargo area through the tailgate, rear cargo panel, or rear door.
A baggage carrier assembly is shown in U.S. Pat. No. 1,575,225 where a pair of cross-connected arms is secured to any suitable part of an automobile at the rear end. A rack is pivotally mounted to one arm by a pivot pin at a first pivot joint. This enables the rack to swing outward in a horizontal plane. The rack has a second and independent pivot joint which enables one portion of the rack to be folded upwards against the rear end of the automobile when not in use.
One disadvantage of the baggage carrier assembly in U.S. Pat. No. 1,575,225, however, is that it uses a single pivot pin at the first pivot joint to swing the rack outward in a horizontal plane. Since the rack secured to the arm at the first pivot joint acts much like a cantilever beam against a supporting wall when the rack is swung outward, the single pivot pin alone must bear loads and stresses similar to those associated with cantilever beams. In particular, the single pivot pin must bear the stress caused by a moment exerted on the pivot pin. The moment is created by a load exerted on the rack, as well as the weight of the rack itself. Although probably sufficient for simple luggage pieces and other lightweight items, the single pivot pin would be incapable of handling heavier loads associated with equipment typically used with trailers, such as electric generators, fuel, and heavy tools and equipment. Swinging open the baggage carrier assembly with a heavier load placed on the rack could result in failure of the pivot pin and cause damage to the baggage carrier assembly and its contents.
In U.S. Pat. No. 3,202,332 a luggage carrier is shown having a pair of support arms bolted to the frame of an automobile and additionally L-bolted to a rear car bumper. An auxiliary trunk is pivotally mounted to one support arm by a single bolt extending through a bottom side wall of the auxiliary trunk at one corner. Additionally, this luggage carrier has a stationary support member spring-mounted on the remote end of the trunk's bottom side. The stationary support member swings down to a fixed vertical position and is used to support the rack when swung outward to an open position. However, unless the vehicle is parked on a flat surface, the stationary support member would be too short or too long.
Similar to U.S. Pat. No. 1,575,225, the luggage carrier in U.S. Pat. No. 3,202,332 is also disadvantaged by the use of a single bolt to pivot the auxiliary trunk on the connecting support arm. The single bolt alone must bear the loads and stresses similar to those found in cantilever beams. Although this luggage carrier provides for a support stand at a remote end of the carrier assembly to mitigate cantilever stresses, it is not particularly designed for use without the support stand. Specifically, the single bolt alone could not durably bear the cantilever loads and stresses if the support stand was continuously, albeit inadvertently, omitted from use. The support stand also has a fixed height which is incapable of adjusting to irregular terrains with various heights. Swinging open the luggage carrier with a heavy load placed on the auxiliary trunk could result in failure of the single bolt pivot joint and cause damage to the luggage carrier and its contents.
In U.S. Pat. No. 4,756,457 a cargo apparatus for "mini-vans" and similar vehicles is shown where a pair of container halves are each hinge-mounted to taillight recesses at the rear corner of a mini-van-type vehicle. Taillight assemblies found in the taillight recesses are removed and replaced with box beams. The box beams are secured inside the taillight recesses by securing each box beam to an angle iron member positioned on the reverse side of a taillight recess wall. The taillight recess wall is thus sandwiched between the box beam and the angle iron member. A hinge base of a hinge assembly is then secured to the box beam, and a receptacle hinge plate of the hinge assembly is secured to a front wall of a container halve. Similar to the disclosures in U.S. Pat. No. 1,575,225 and U.S. Pat. No. 3,202,332, this cargo apparatus is also not designed or intended to support heavy loads. Since the taillight recess wall is comprised of sheet-metal, it provides a weak support point for securing the cargo apparatus. The taillight recess wall would easily fatigue and deform under the heavy loads typically associated with trailers. And in fact, two separate hinges are required to support the cargo apparatus. Each hinge supports only one-half of the cargo apparatus. And each hinged part only extends halfway across the back of the vehicle.
Finally in U.S. Pat. No. 5,544,799 a swing away cargo carrier assembly is shown for use with a vehicle having a receiver-type hitch at the rear end. A main support member is inserted into the receiver-type hitch. A main extension arm is fixedly attached to the main support member and extends laterally along the rear of the vehicle. A pivot support member having a C-shaped cross-section is fixedly attached to and extends rearwardly from the main extension arm. And finally, a swing arm is pivotally mounted to the pivot support member by a single bolt. This allows the swing arm to swing outwardly from the rear end of a vehicle. The disadvantage of this design is its use of a single bolt at its pivot joint. As discussed previously, a single bolt is generally inadequate for supporting heavy loads. Using a single bolt increases the risk of fatigue and failure at the pivot joint when the swing arm is fully extended with a heavy load.
As can be seen from the above prior disclosures, there are many practical benefits to a swinging carrier assembly mounted to the rear end of a vehicle. They all provide a way to carry and/or store additional cargo on the exterior of a vehicle. They also provide a way of swinging a receptacle component away from the rear end of a vehicle in order to allow access to the rear cargo area of the vehicle. Generally, however, the swinging carrier assemblies disclosed in the prior art are not designed or intended for use with trailers. They are not suited to meet the particular needs and greater demands typically required by trailers.
In particular, articles and equipment commonly carried and/or stored in trailers are different and impart a much heavier load than those commonly carried and/or stored in passenger vehicles. Equipment typically carried in trailers include electric generators, fuel tanks, and the like. However, gasoline tanks and gasoline powered apparatus such as electric generators are not permitted to be carried within a trailer since they comprise a fire/explosive hazard. Electric generators, fuel tanks, and similar equipment are thus, of necessity, items carried only outside of the trailer compartment. And since electric generators and fuel tanks impart much heavier loads, swinging carrier assemblies used with trailers require greater support and durability at the pivot joints. Greater support and durability are especially required when the container component is swung open because of the cantilever-like loads and stresses which are created at the pivot joint.
To summarize, there is a need for an improved swinging carrier assembly intended and especially designed for use with trailers. The existing prior disclosures lack the durability to withstand the greater cantilever-like loads and stresses associated with equipment typically used with trailers.